On 8/23/24 22:00, Wesley Cheng wrote:
> From: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
>
> Expose xhci_stop_endpoint_sync() which is a synchronous variant of
> xhci_queue_stop_endpoint(). This is useful for client drivers that are
> using the secondary interrupters, and need to stop/clean up the current
> session. The stop endpoint command handler will also take care of cleaning
> up the ring.
>
> Signed-off-by: Mathias Nyman <mathias.nyman@xxxxxxxxxxxxxxx>
> Signed-off-by: Wesley Cheng <quic_wcheng@xxxxxxxxxxx>
> ---
> drivers/usb/host/xhci.c | 39 +++++++++++++++++++++++++++++++++++++++
> drivers/usb/host/xhci.h | 2 ++
> 2 files changed, 41 insertions(+)
>
> diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
> index 37eb37b0affa..3a051ed32907 100644
> --- a/drivers/usb/host/xhci.c
> +++ b/drivers/usb/host/xhci.c
> @@ -2784,6 +2784,45 @@ static int xhci_reserve_bandwidth(struct xhci_hcd *xhci,
> return -ENOMEM;
> }
>
> +/*
> + * Synchronous XHCI stop endpoint helper. Issues the stop endpoint command and
> + * waits for the command completion before returning.
> + */
> +int xhci_stop_endpoint_sync(struct xhci_hcd *xhci, struct xhci_virt_ep *ep, int suspend,
> + gfp_t gfp_flags)
> +{
> + struct xhci_command *command;
> + unsigned long flags;
> + int ret;
> +
> + command = xhci_alloc_command(xhci, true, gfp_flags);
> + if (!command)
> + return -ENOMEM;
> +
> + spin_lock_irqsave(&xhci->lock, flags);
> + ret = xhci_queue_stop_endpoint(xhci, command, ep->vdev->slot_id,
> + ep->ep_index, suspend);
> + if (ret < 0) {
> + spin_unlock_irqrestore(&xhci->lock, flags);
> + goto out;
> + }
> +
> + xhci_ring_cmd_db(xhci);
> + spin_unlock_irqrestore(&xhci->lock, flags);
> +
> + wait_for_completion(command->completion);
> +
> + if (command->status == COMP_COMMAND_ABORTED ||
> + command->status == COMP_COMMAND_RING_STOPPED) {
> + xhci_warn(xhci, "Timeout while waiting for stop endpoint command\n");
nit-pick: is this really a timeout? In that case you would have used
wait_for_completion_timeout(), no?
> + ret = -ETIME;
> + }
> +out:
> + xhci_free_command(xhci, command);
> +
> + return ret;
> +}
> +EXPORT_SYMBOL_GPL(xhci_stop_endpoint_sync);
>
> /* Issue a configure endpoint command or evaluate context command
> * and wait for it to finish.
> diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h
> index 30415158ed3c..1c6126ed55b0 100644
> --- a/drivers/usb/host/xhci.h
> +++ b/drivers/usb/host/xhci.h
> @@ -1914,6 +1914,8 @@ void xhci_ring_doorbell_for_active_rings(struct xhci_hcd *xhci,
> void xhci_cleanup_command_queue(struct xhci_hcd *xhci);
> void inc_deq(struct xhci_hcd *xhci, struct xhci_ring *ring);
> unsigned int count_trbs(u64 addr, u64 len);
> +int xhci_stop_endpoint_sync(struct xhci_hcd *xhci, struct xhci_virt_ep *ep,
> + int suspend, gfp_t gfp_flags);
>
> /* xHCI roothub code */
> void xhci_set_link_state(struct xhci_hcd *xhci, struct xhci_port *port,
